Surgical sutures are requested to have properties of nontoxicity, appropriate smoothness, high knot strength, etc. In order to impart the properties to surgical sutures, proposed are sutures prepared by coating suture bodies consisting of bioabsorbable polymers such as homopolymer or copolymer of lactide, glycolide, etc., with higher fatty acid salts (U.S. Pat. No. 4,532,929); compositions comprising higher fatty acid salts and film-forming polymers, such as poly(p-dioxanone), polycaprolactone and polyethyleneoxide (U.S. Pat. Nos. 4,201,216; 4,624,256; 5,378,540; and 5,380,780); sucrose fatty acid esters (U.S. Pat. No. 4,844,067).
When only higher fatty acid salts are attached to suture bodies, however, a problem of easy strip of coating layer arises. Although sutures coated with compositions comprising higher fatty acid salts and film-forming polymers, such as poly(p-dioxanone), polycaprolactone and polyethyleneoxide, have improved lubricating properties, said sutures have a problem of decreased knot strength. Sutures coated with sucrose fatty acid esters are fair in properties of smoothness and knot strength. However, said sutures are requested to have further improved properties.
Maintenance of knot strength of sutures becomes difficult in proportional to improvement of smoothness of sutures leading to higher slip properties thereof.
It is an object of the invention to provide surgical sutures having outstanding properties in both smoothness and knot strength without toxicity.